Thanasimus

Chapman, Eric G., Leavengood, John M. & Dupuis, Julian R., 2025, The Cleridae and Thanerocleridae of eastern North America, with illustrated keys, updated distributions, and special emphasis on the Kentucky fauna, Zootaxa 5639 (1), pp. 1-88 : 31

Key to species of Thanasimus ( Clerinae ) in eastern North America

1. Basal 4 th of elytra with very coarse, dense punctures (appearing almost rugose), punctures not in discernable rows ( A); head, pronotum and base of elytra entirely red to orange; elytra with anterior-most fascia of white hairs with no dark coloration anterior to this fascia ( B—arrow); larger species,> 10 mm (usually around 15 mm in total length), noticeably larger than the other species ( E—middle row).................................................. Thanasimus trifasciatus (Say)

1’. Basal 4 th of elytra with finer, less dense punctation arranged in rows ( C, D); color of head, pronotum and base of elytra variable, but anterior-most white fascia of elytra almost always bordered on both sides by dark brown to black markings ( C, D; except in some specimens of undatulus ); smaller species (< 10 mm in total length; E—top & bottom rows)................... 2

2(1’). Head, pronotum and base of elytra entirely orange (head sometimes a little darker but not black, A); anterior white fascia of elytra not extending along suture to near elytral base ( A—arrow); vestiture of head not contrasting color with the orange-brown color of this region........................................................... Thanasimus dubius (Fabricius)

2’. Head, pronotum and/or elytral base with some black (minimally with head black ( B), often entirely black ( C); anterior white fascia of elytra extending forward along suture to near elytral base ( B, C—arrows, even if only faintly); vestiture of head often white and contrasting with the usually black color of this region ( C—arrow on head)........ Thanasimus undatulus (Say)